The prevalence of heart disease, diabetes and obesity have increased dramatically in Alaska Natives and represent unique opportunities for research related to the health status of this population. Family structure data and refined or extreme phenotypes which are extremely helpful in efforts to map and clone genes contributing to complex traits such as obesity have not been determined in this population. Analysis of the genetics of obesity in Alaska Natives will be conducted in a collaborative study with scientists at the New York Obesity Research Center to evaluate this population as a potential resource and identify genetic risk factors associated with obesity. The proposed research is designed to elucidate both the feasibility of and develop strategies for the identification of genes contributing to obesity in Alaska Natives. The specific aims include: determining the family structure, size and degree of consanguinity and apparent genetic admixture in Alaska Natives, conducting quantitative genetic analyses using the "unmeasured" genotype approach, investigating the role(s) of obesity candidate genes by parametric and nonparametric based association methods, and by obtaining training in the principles, accuracy, precision and applications of common body composition methodologies. The long term goal of the proposed research is to provide the training and preliminary data necessary to evaluate the possibility of conducting a thorough gene mapping effort in this population.